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flutter_flutter/sky/engine/core/rendering/RenderParagraph.cpp
Adam Barth 9c09565712 Update paths to account for buildroot
2016-08-09 13:52:15 -07:00

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// Copyright 2014 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#include "flutter/sky/engine/core/rendering/RenderParagraph.h"
#include "flutter/sky/engine/core/rendering/BidiRunForLine.h"
#include "flutter/sky/engine/core/rendering/InlineIterator.h"
#include "flutter/sky/engine/core/rendering/RenderLayer.h"
#include "flutter/sky/engine/core/rendering/RenderObjectInlines.h"
#include "flutter/sky/engine/core/rendering/RenderView.h"
#include "flutter/sky/engine/core/rendering/TextRunConstructor.h"
#include "flutter/sky/engine/core/rendering/VerticalPositionCache.h"
#include "flutter/sky/engine/core/rendering/line/BreakingContextInlineHeaders.h"
#include "flutter/sky/engine/core/rendering/line/LineLayoutState.h"
#include "flutter/sky/engine/core/rendering/line/LineWidth.h"
#include "flutter/sky/engine/core/rendering/line/RenderTextInfo.h"
#include "flutter/sky/engine/core/rendering/line/WordMeasurement.h"
#include "flutter/sky/engine/platform/fonts/Character.h"
#include "flutter/sky/engine/platform/text/BidiResolver.h"
#include "flutter/sky/engine/wtf/RefCountedLeakCounter.h"
#include "flutter/sky/engine/wtf/StdLibExtras.h"
#include "flutter/sky/engine/wtf/Vector.h"
#include "flutter/sky/engine/wtf/unicode/CharacterNames.h"
namespace blink {
using namespace WTF::Unicode;
RenderParagraph::RenderParagraph()
{
}
RenderParagraph::~RenderParagraph()
{
}
const char* RenderParagraph::renderName() const
{
return "RenderParagraph";
}
LayoutUnit RenderParagraph::logicalLeftSelectionOffset(RenderBlock* rootBlock, LayoutUnit position)
{
LayoutUnit logicalLeft = logicalLeftOffsetForLine(false);
if (logicalLeft == logicalLeftOffsetForContent())
return RenderBlock::logicalLeftSelectionOffset(rootBlock, position);
RenderBlock* cb = this;
while (cb != rootBlock) {
logicalLeft += cb->logicalLeft();
cb = cb->containingBlock();
}
return logicalLeft;
}
LayoutUnit RenderParagraph::logicalRightSelectionOffset(RenderBlock* rootBlock, LayoutUnit position)
{
LayoutUnit logicalRight = logicalRightOffsetForLine(false);
if (logicalRight == logicalRightOffsetForContent())
return RenderBlock::logicalRightSelectionOffset(rootBlock, position);
RenderBlock* cb = this;
while (cb != rootBlock) {
logicalRight += cb->logicalLeft();
cb = cb->containingBlock();
}
return logicalRight;
}
RootInlineBox* RenderParagraph::lineAtIndex(int i) const
{
ASSERT(i >= 0);
for (RootInlineBox* box = firstRootBox(); box; box = box->nextRootBox()) {
if (!i--)
return box;
}
return 0;
}
int RenderParagraph::lineCount(const RootInlineBox* stopRootInlineBox, bool* found) const
{
int count = 0;
for (RootInlineBox* box = firstRootBox(); box; box = box->nextRootBox()) {
count++;
if (box == stopRootInlineBox) {
if (found)
*found = true;
break;
}
}
return count;
}
void RenderParagraph::deleteLineBoxTree()
{
m_lineBoxes.deleteLineBoxTree();
}
GapRects RenderParagraph::inlineSelectionGaps(RenderBlock* rootBlock, const LayoutPoint& rootBlockPhysicalPosition, const LayoutSize& offsetFromRootBlock,
LayoutUnit& lastLogicalTop, LayoutUnit& lastLogicalLeft, LayoutUnit& lastLogicalRight, const PaintInfo* paintInfo)
{
GapRects result;
bool containsStart = selectionState() == SelectionStart || selectionState() == SelectionBoth;
if (!firstLineBox()) {
if (containsStart) {
// Go ahead and update our lastLogicalTop to be the bottom of the block. <hr>s or empty blocks with height can trip this
// case.
lastLogicalTop = rootBlock->blockDirectionOffset(offsetFromRootBlock) + logicalHeight();
lastLogicalLeft = logicalLeftSelectionOffset(rootBlock, logicalHeight());
lastLogicalRight = logicalRightSelectionOffset(rootBlock, logicalHeight());
}
return result;
}
RootInlineBox* lastSelectedLine = 0;
RootInlineBox* curr;
for (curr = firstRootBox(); curr && !curr->hasSelectedChildren(); curr = curr->nextRootBox()) { }
// Now paint the gaps for the lines.
for (; curr && curr->hasSelectedChildren(); curr = curr->nextRootBox()) {
LayoutUnit selTop = curr->selectionTopAdjustedForPrecedingBlock();
LayoutUnit selHeight = curr->selectionHeightAdjustedForPrecedingBlock();
if (!containsStart && !lastSelectedLine && selectionState() != SelectionStart && selectionState() != SelectionBoth) {
result.uniteCenter(blockSelectionGap(rootBlock, rootBlockPhysicalPosition, offsetFromRootBlock, lastLogicalTop,
lastLogicalLeft, lastLogicalRight, selTop, paintInfo));
}
LayoutRect logicalRect(curr->logicalLeft(), selTop, curr->logicalWidth(), selTop + selHeight);
logicalRect.move(offsetFromRootBlock);
LayoutRect physicalRect = rootBlock->logicalRectToPhysicalRect(rootBlockPhysicalPosition, logicalRect);
if (!paintInfo || (physicalRect.y() < paintInfo->rect.maxY() && physicalRect.maxY() > paintInfo->rect.y()))
result.unite(curr->lineSelectionGap(rootBlock, rootBlockPhysicalPosition, offsetFromRootBlock, selTop, selHeight, paintInfo));
lastSelectedLine = curr;
}
if (containsStart && !lastSelectedLine) {
// VisibleSelection must start just after our last line.
lastSelectedLine = lastRootBox();
}
if (lastSelectedLine && selectionState() != SelectionEnd && selectionState() != SelectionBoth) {
// Go ahead and update our lastY to be the bottom of the last selected line.
lastLogicalTop = rootBlock->blockDirectionOffset(offsetFromRootBlock) + lastSelectedLine->selectionBottom();
lastLogicalLeft = logicalLeftSelectionOffset(rootBlock, lastSelectedLine->selectionBottom());
lastLogicalRight = logicalRightSelectionOffset(rootBlock, lastSelectedLine->selectionBottom());
}
return result;
}
void RenderParagraph::addOverflowFromChildren()
{
LayoutUnit endPadding = hasOverflowClip() ? paddingEnd() : LayoutUnit();
for (RootInlineBox* curr = firstRootBox(); curr; curr = curr->nextRootBox()) {
addLayoutOverflow(curr->paddedLayoutOverflowRect(endPadding));
LayoutRect visualOverflow = curr->visualOverflowRect(curr->lineTop(), curr->lineBottom());
addContentsVisualOverflow(visualOverflow);
}
}
void RenderParagraph::simplifiedNormalFlowLayout()
{
ListHashSet<RootInlineBox*> lineBoxes;
for (InlineWalker walker(this); !walker.atEnd(); walker.advance()) {
RenderObject* o = walker.current();
if (!o->isOutOfFlowPositioned() && o->isReplaced()) {
o->layoutIfNeeded();
if (toRenderBox(o)->inlineBoxWrapper()) {
RootInlineBox& box = toRenderBox(o)->inlineBoxWrapper()->root();
lineBoxes.add(&box);
}
} else if (o->isText() || (o->isRenderInline() && !walker.atEndOfInline())) {
o->clearNeedsLayout();
}
}
// FIXME: Glyph overflow will get lost in this case, but not really a big deal.
GlyphOverflowAndFallbackFontsMap textBoxDataMap;
for (ListHashSet<RootInlineBox*>::const_iterator it = lineBoxes.begin(); it != lineBoxes.end(); ++it) {
RootInlineBox* box = *it;
box->computeOverflow(box->lineTop(), box->lineBottom(), textBoxDataMap);
}
}
void RenderParagraph::paintChildren(PaintInfo& paintInfo, const LayoutPoint& paintOffset, Vector<RenderBox*>& layers)
{
m_lineBoxes.paint(this, paintInfo, paintOffset, layers);
for (RenderObject* child = firstChild(); child; child = child->nextSibling()) {
// TODO(ojan): This is wrong at the moment. Inlines can have self painting
// layers as well. Either make inlines with self-painting layers work or
// don't allow inlines to be self painting.
if (child->isBox()) {
RenderBox* box = toRenderBox(child);
if (box->hasSelfPaintingLayer())
layers.append(box);
}
}
}
bool RenderParagraph::hitTestContents(const HitTestRequest& request, HitTestResult& result, const HitTestLocation& locationInContainer, const LayoutPoint& accumulatedOffset)
{
return m_lineBoxes.hitTest(this, request, result, locationInContainer, accumulatedOffset);
}
void RenderParagraph::markLinesDirtyInBlockRange(LayoutUnit logicalTop, LayoutUnit logicalBottom, RootInlineBox* highest)
{
if (logicalTop >= logicalBottom)
return;
RootInlineBox* lowestDirtyLine = lastRootBox();
RootInlineBox* afterLowest = lowestDirtyLine;
while (lowestDirtyLine && lowestDirtyLine->lineBottomWithLeading() >= logicalBottom && logicalBottom < LayoutUnit::max()) {
afterLowest = lowestDirtyLine;
lowestDirtyLine = lowestDirtyLine->prevRootBox();
}
while (afterLowest && afterLowest != highest && (afterLowest->lineBottomWithLeading() >= logicalTop || afterLowest->lineBottomWithLeading() < 0)) {
afterLowest->markDirty();
afterLowest = afterLowest->prevRootBox();
}
}
static void updateLogicalWidthForLeftAlignedBlock(bool isLeftToRightDirection, BidiRun* trailingSpaceRun, float& logicalLeft, float& totalLogicalWidth, float availableLogicalWidth)
{
// The direction of the block should determine what happens with wide lines.
// In particular with RTL blocks, wide lines should still spill out to the left.
if (isLeftToRightDirection) {
if (totalLogicalWidth > availableLogicalWidth && trailingSpaceRun)
trailingSpaceRun->m_box->setLogicalWidth(std::max<float>(0, trailingSpaceRun->m_box->logicalWidth() - totalLogicalWidth + availableLogicalWidth));
return;
}
if (trailingSpaceRun)
trailingSpaceRun->m_box->setLogicalWidth(0);
else if (totalLogicalWidth > availableLogicalWidth)
logicalLeft -= (totalLogicalWidth - availableLogicalWidth);
}
static void updateLogicalWidthForRightAlignedBlock(bool isLeftToRightDirection, BidiRun* trailingSpaceRun, float& logicalLeft, float& totalLogicalWidth, float availableLogicalWidth)
{
// Wide lines spill out of the block based off direction.
// So even if text-align is right, if direction is LTR, wide lines should overflow out of the right
// side of the block.
if (isLeftToRightDirection) {
if (trailingSpaceRun) {
totalLogicalWidth -= trailingSpaceRun->m_box->logicalWidth();
trailingSpaceRun->m_box->setLogicalWidth(0);
}
if (totalLogicalWidth < availableLogicalWidth)
logicalLeft += availableLogicalWidth - totalLogicalWidth;
return;
}
if (totalLogicalWidth > availableLogicalWidth && trailingSpaceRun) {
trailingSpaceRun->m_box->setLogicalWidth(std::max<float>(0, trailingSpaceRun->m_box->logicalWidth() - totalLogicalWidth + availableLogicalWidth));
totalLogicalWidth -= trailingSpaceRun->m_box->logicalWidth();
} else
logicalLeft += availableLogicalWidth - totalLogicalWidth;
}
static void updateLogicalWidthForCenterAlignedBlock(bool isLeftToRightDirection, BidiRun* trailingSpaceRun, float& logicalLeft, float& totalLogicalWidth, float availableLogicalWidth)
{
float trailingSpaceWidth = 0;
if (trailingSpaceRun) {
totalLogicalWidth -= trailingSpaceRun->m_box->logicalWidth();
trailingSpaceWidth = std::min(trailingSpaceRun->m_box->logicalWidth(), (availableLogicalWidth - totalLogicalWidth + 1) / 2);
trailingSpaceRun->m_box->setLogicalWidth(std::max<float>(0, trailingSpaceWidth));
}
if (isLeftToRightDirection)
logicalLeft += std::max<float>((availableLogicalWidth - totalLogicalWidth) / 2, 0);
else
logicalLeft += totalLogicalWidth > availableLogicalWidth ? (availableLogicalWidth - totalLogicalWidth) : (availableLogicalWidth - totalLogicalWidth) / 2 - trailingSpaceWidth;
}
void RenderParagraph::updateLogicalWidthForAlignment(const ETextAlign& textAlign, const RootInlineBox* rootInlineBox, BidiRun* trailingSpaceRun, float& logicalLeft, float& totalLogicalWidth, float& availableLogicalWidth, unsigned expansionOpportunityCount)
{
TextDirection direction;
if (rootInlineBox && rootInlineBox->renderer().style()->unicodeBidi() == Plaintext)
direction = rootInlineBox->direction();
else
direction = style()->direction();
// Armed with the total width of the line (without justification),
// we now examine our text-align property in order to determine where to position the
// objects horizontally. The total width of the line can be increased if we end up
// justifying text.
switch (textAlign) {
case LEFT:
updateLogicalWidthForLeftAlignedBlock(style()->isLeftToRightDirection(), trailingSpaceRun, logicalLeft, totalLogicalWidth, availableLogicalWidth);
break;
case RIGHT:
updateLogicalWidthForRightAlignedBlock(style()->isLeftToRightDirection(), trailingSpaceRun, logicalLeft, totalLogicalWidth, availableLogicalWidth);
break;
case CENTER:
updateLogicalWidthForCenterAlignedBlock(style()->isLeftToRightDirection(), trailingSpaceRun, logicalLeft, totalLogicalWidth, availableLogicalWidth);
break;
case JUSTIFY:
adjustInlineDirectionLineBounds(expansionOpportunityCount, logicalLeft, availableLogicalWidth);
if (expansionOpportunityCount) {
if (trailingSpaceRun) {
totalLogicalWidth -= trailingSpaceRun->m_box->logicalWidth();
trailingSpaceRun->m_box->setLogicalWidth(0);
}
break;
}
// Fall through
case TASTART:
if (direction == LTR)
updateLogicalWidthForLeftAlignedBlock(style()->isLeftToRightDirection(), trailingSpaceRun, logicalLeft, totalLogicalWidth, availableLogicalWidth);
else
updateLogicalWidthForRightAlignedBlock(style()->isLeftToRightDirection(), trailingSpaceRun, logicalLeft, totalLogicalWidth, availableLogicalWidth);
break;
case TAEND:
if (direction == LTR)
updateLogicalWidthForRightAlignedBlock(style()->isLeftToRightDirection(), trailingSpaceRun, logicalLeft, totalLogicalWidth, availableLogicalWidth);
else
updateLogicalWidthForLeftAlignedBlock(style()->isLeftToRightDirection(), trailingSpaceRun, logicalLeft, totalLogicalWidth, availableLogicalWidth);
break;
}
}
RootInlineBox* RenderParagraph::createAndAppendRootInlineBox()
{
RootInlineBox* rootBox = createRootInlineBox();
m_lineBoxes.appendLineBox(rootBox);
return rootBox;
}
RootInlineBox* RenderParagraph::createRootInlineBox()
{
return new RootInlineBox(*this);
}
InlineBox* RenderParagraph::createInlineBoxForRenderer(RenderObject* obj, bool isRootLineBox, bool isOnlyRun)
{
if (isRootLineBox)
return toRenderParagraph(obj)->createAndAppendRootInlineBox();
if (obj->isText()) {
InlineTextBox* textBox = toRenderText(obj)->createInlineTextBox();
// We only treat a box as text for a <br> if we are on a line by ourself or in strict mode
// (Note the use of strict mode. In "almost strict" mode, we don't treat the box for <br> as text.)
return textBox;
}
if (obj->isBox())
return toRenderBox(obj)->createInlineBox();
return toRenderInline(obj)->createAndAppendInlineFlowBox();
}
static inline void dirtyLineBoxesForRenderer(RenderObject* o, bool fullLayout)
{
if (o->isText()) {
RenderText* renderText = toRenderText(o);
renderText->dirtyLineBoxes(fullLayout);
} else
toRenderInline(o)->dirtyLineBoxes(fullLayout);
}
static bool parentIsConstructedOrHaveNext(InlineFlowBox* parentBox)
{
do {
if (parentBox->isConstructed() || parentBox->nextOnLine())
return true;
parentBox = parentBox->parent();
} while (parentBox);
return false;
}
InlineFlowBox* RenderParagraph::createLineBoxes(RenderObject* obj, const LineInfo& lineInfo, InlineBox* childBox)
{
// See if we have an unconstructed line box for this object that is also
// the last item on the line.
unsigned lineDepth = 1;
InlineFlowBox* parentBox = 0;
InlineFlowBox* result = 0;
bool hasDefaultLineBoxContain = style()->lineBoxContain() == RenderStyle::initialLineBoxContain();
do {
ASSERT_WITH_SECURITY_IMPLICATION(obj->isRenderInline() || obj == this);
RenderInline* inlineFlow = (obj != this) ? toRenderInline(obj) : 0;
// Get the last box we made for this render object.
parentBox = inlineFlow ? inlineFlow->lastLineBox() : toRenderBlock(obj)->lastLineBox();
// If this box or its ancestor is constructed then it is from a previous line, and we need
// to make a new box for our line. If this box or its ancestor is unconstructed but it has
// something following it on the line, then we know we have to make a new box
// as well. In this situation our inline has actually been split in two on
// the same line (this can happen with very fancy language mixtures).
bool constructedNewBox = false;
bool allowedToConstructNewBox = !hasDefaultLineBoxContain || !inlineFlow || inlineFlow->alwaysCreateLineBoxes();
bool canUseExistingParentBox = parentBox && !parentIsConstructedOrHaveNext(parentBox);
if (allowedToConstructNewBox && !canUseExistingParentBox) {
// We need to make a new box for this render object. Once
// made, we need to place it at the end of the current line.
InlineBox* newBox = createInlineBoxForRenderer(obj, obj == this);
ASSERT_WITH_SECURITY_IMPLICATION(newBox->isInlineFlowBox());
parentBox = toInlineFlowBox(newBox);
parentBox->setFirstLineStyleBit(lineInfo.isFirstLine());
if (!hasDefaultLineBoxContain)
parentBox->clearDescendantsHaveSameLineHeightAndBaseline();
constructedNewBox = true;
}
if (constructedNewBox || canUseExistingParentBox) {
if (!result)
result = parentBox;
// If we have hit the block itself, then |box| represents the root
// inline box for the line, and it doesn't have to be appended to any parent
// inline.
if (childBox)
parentBox->addToLine(childBox);
if (!constructedNewBox || obj == this)
break;
childBox = parentBox;
}
// If we've exceeded our line depth, then jump straight to the root and skip all the remaining
// intermediate inline flows.
obj = (++lineDepth >= cMaxLineDepth) ? this : obj->parent();
} while (true);
return result;
}
template <typename CharacterType>
static inline bool endsWithASCIISpaces(const CharacterType* characters, unsigned pos, unsigned end)
{
while (isASCIISpace(characters[pos])) {
pos++;
if (pos >= end)
return true;
}
return false;
}
static bool reachedEndOfTextRenderer(const BidiRunList<BidiRun>& bidiRuns)
{
BidiRun* run = bidiRuns.logicallyLastRun();
if (!run)
return true;
unsigned pos = run->stop();
RenderObject* r = run->m_object;
if (!r->isText())
return false;
RenderText* renderText = toRenderText(r);
unsigned length = renderText->textLength();
if (pos >= length)
return true;
if (renderText->is8Bit())
return endsWithASCIISpaces(renderText->characters8(), pos, length);
return endsWithASCIISpaces(renderText->characters16(), pos, length);
}
RootInlineBox* RenderParagraph::constructLine(BidiRunList<BidiRun>& bidiRuns, const LineInfo& lineInfo)
{
ASSERT(bidiRuns.firstRun());
bool rootHasSelectedChildren = false;
InlineFlowBox* parentBox = 0;
int runCount = bidiRuns.runCount() - lineInfo.runsFromLeadingWhitespace();
for (BidiRun* r = bidiRuns.firstRun(); r; r = r->next()) {
// Create a box for our object.
bool isOnlyRun = (runCount == 1);
if (runCount == 2)
isOnlyRun = false;
if (lineInfo.isEmpty())
continue;
InlineBox* box = createInlineBoxForRenderer(r->m_object, false, isOnlyRun);
r->m_box = box;
ASSERT(box);
if (!box)
continue;
if (!rootHasSelectedChildren && box->renderer().selectionState() != RenderObject::SelectionNone)
rootHasSelectedChildren = true;
// If we have no parent box yet, or if the run is not simply a sibling,
// then we need to construct inline boxes as necessary to properly enclose the
// run's inline box. Segments can only be siblings at the root level, as
// they are positioned separately.
if (!parentBox || parentBox->renderer() != r->m_object->parent()) {
// Create new inline boxes all the way back to the appropriate insertion point.
parentBox = createLineBoxes(r->m_object->parent(), lineInfo, box);
} else {
// Append the inline box to this line.
parentBox->addToLine(box);
}
box->setBidiLevel(r->level());
if (box->isInlineTextBox()) {
InlineTextBox* text = toInlineTextBox(box);
text->setStart(r->m_start);
text->setLen(r->m_stop - r->m_start);
text->setDirOverride(r->dirOverride());
if (r->m_hasHyphen)
text->setHasHyphen(true);
}
}
ASSERT(lastLineBox() && !lastLineBox()->isConstructed());
// Set the m_selectedChildren flag on the root inline box if one of the leaf inline box
// from the bidi runs walk above has a selection state.
if (rootHasSelectedChildren)
lastLineBox()->root().setHasSelectedChildren(true);
// Set bits on our inline flow boxes that indicate which sides should
// paint borders/margins/padding. This knowledge will ultimately be used when
// we determine the horizontal positions and widths of all the inline boxes on
// the line.
bool isLogicallyLastRunWrapped = bidiRuns.logicallyLastRun()->m_object && bidiRuns.logicallyLastRun()->m_object->isText() ? !reachedEndOfTextRenderer(bidiRuns) : true;
lastLineBox()->determineSpacingForFlowBoxes(lineInfo.isLastLine(), isLogicallyLastRunWrapped, bidiRuns.logicallyLastRun()->m_object);
// Now mark the line boxes as being constructed.
lastLineBox()->setConstructed();
// Return the last line.
return lastRootBox();
}
ETextAlign RenderParagraph::textAlignmentForLine(bool endsWithSoftBreak) const
{
ETextAlign alignment = style()->textAlign();
if (endsWithSoftBreak)
return alignment;
return (alignment == JUSTIFY) ? TASTART : alignment;
}
static inline void setLogicalWidthForTextRun(RootInlineBox* lineBox, BidiRun* run, RenderText* renderer, float xPos, const LineInfo& lineInfo,
GlyphOverflowAndFallbackFontsMap& textBoxDataMap, VerticalPositionCache& verticalPositionCache, WordMeasurements& wordMeasurements)
{
HashSet<const SimpleFontData*> fallbackFonts;
GlyphOverflow glyphOverflow;
const Font& font = renderer->style(lineInfo.isFirstLine())->font();
// Always compute glyph overflow if the block's line-box-contain value is "glyphs".
if (lineBox->fitsToGlyphs()) {
// If we don't stick out of the root line's font box, then don't bother computing our glyph overflow. This optimization
// will keep us from computing glyph bounds in nearly all cases.
bool includeRootLine = lineBox->includesRootLineBoxFontOrLeading();
int baselineShift = lineBox->verticalPositionForBox(run->m_box, verticalPositionCache);
int rootDescent = includeRootLine ? font.fontMetrics().descent() : 0;
int rootAscent = includeRootLine ? font.fontMetrics().ascent() : 0;
int boxAscent = font.fontMetrics().ascent() - baselineShift;
int boxDescent = font.fontMetrics().descent() + baselineShift;
if (boxAscent > rootDescent || boxDescent > rootAscent)
glyphOverflow.computeBounds = true;
}
LayoutUnit hyphenWidth = 0;
if (toInlineTextBox(run->m_box)->hasHyphen()) {
const Font& font = renderer->style(lineInfo.isFirstLine())->font();
hyphenWidth = measureHyphenWidth(renderer, font, run->direction());
}
float measuredWidth = 0;
bool kerningIsEnabled = font.fontDescription().typesettingFeatures() & Kerning;
bool canUseSimpleFontCodePath = renderer->canUseSimpleFontCodePath();
// Since we don't cache glyph overflows, we need to re-measure the run if
// the style is linebox-contain: glyph.
if (!lineBox->fitsToGlyphs() && canUseSimpleFontCodePath) {
int lastEndOffset = run->m_start;
for (size_t i = 0, size = wordMeasurements.size(); i < size && lastEndOffset < run->m_stop; ++i) {
const WordMeasurement& wordMeasurement = wordMeasurements[i];
if (wordMeasurement.width <=0 || wordMeasurement.startOffset == wordMeasurement.endOffset)
continue;
if (wordMeasurement.renderer != renderer || wordMeasurement.startOffset != lastEndOffset || wordMeasurement.endOffset > run->m_stop)
continue;
lastEndOffset = wordMeasurement.endOffset;
if (kerningIsEnabled && lastEndOffset == run->m_stop) {
int wordLength = lastEndOffset - wordMeasurement.startOffset;
measuredWidth += renderer->width(wordMeasurement.startOffset, wordLength, xPos, run->direction(), lineInfo.isFirstLine());
if (i > 0 && wordLength == 1 && renderer->characterAt(wordMeasurement.startOffset) == ' ')
measuredWidth += renderer->style()->wordSpacing();
} else
measuredWidth += wordMeasurement.width;
if (!wordMeasurement.fallbackFonts.isEmpty()) {
HashSet<const SimpleFontData*>::const_iterator end = wordMeasurement.fallbackFonts.end();
for (HashSet<const SimpleFontData*>::const_iterator it = wordMeasurement.fallbackFonts.begin(); it != end; ++it)
fallbackFonts.add(*it);
}
}
if (measuredWidth && lastEndOffset != run->m_stop) {
// If we don't have enough cached data, we'll measure the run again.
measuredWidth = 0;
fallbackFonts.clear();
}
}
if (!measuredWidth)
measuredWidth = renderer->width(run->m_start, run->m_stop - run->m_start, xPos, run->direction(), lineInfo.isFirstLine(), &fallbackFonts, &glyphOverflow);
run->m_box->setLogicalWidth(measuredWidth + hyphenWidth);
if (!fallbackFonts.isEmpty()) {
ASSERT(run->m_box->isText());
GlyphOverflowAndFallbackFontsMap::ValueType* it = textBoxDataMap.add(toInlineTextBox(run->m_box), std::make_pair(Vector<const SimpleFontData*>(), GlyphOverflow())).storedValue;
ASSERT(it->value.first.isEmpty());
copyToVector(fallbackFonts, it->value.first);
run->m_box->parent()->clearDescendantsHaveSameLineHeightAndBaseline();
}
if (!glyphOverflow.isZero()) {
ASSERT(run->m_box->isText());
GlyphOverflowAndFallbackFontsMap::ValueType* it = textBoxDataMap.add(toInlineTextBox(run->m_box), std::make_pair(Vector<const SimpleFontData*>(), GlyphOverflow())).storedValue;
it->value.second = glyphOverflow;
run->m_box->clearKnownToHaveNoOverflow();
}
}
static inline void computeExpansionForJustifiedText(BidiRun* firstRun, BidiRun* trailingSpaceRun, Vector<unsigned, 16>& expansionOpportunities, unsigned expansionOpportunityCount, float& totalLogicalWidth, float availableLogicalWidth)
{
if (!expansionOpportunityCount || availableLogicalWidth <= totalLogicalWidth)
return;
size_t i = 0;
for (BidiRun* r = firstRun; r; r = r->next()) {
if (!r->m_box || r == trailingSpaceRun)
continue;
if (r->m_object->isText()) {
unsigned opportunitiesInRun = expansionOpportunities[i++];
ASSERT(opportunitiesInRun <= expansionOpportunityCount);
// Don't justify for white-space: pre.
if (r->m_object->style()->whiteSpace() != PRE) {
InlineTextBox* textBox = toInlineTextBox(r->m_box);
int expansion = (availableLogicalWidth - totalLogicalWidth) * opportunitiesInRun / expansionOpportunityCount;
textBox->setExpansion(expansion);
totalLogicalWidth += expansion;
}
expansionOpportunityCount -= opportunitiesInRun;
if (!expansionOpportunityCount)
break;
}
}
}
static void updateLogicalInlinePositions(RenderParagraph* block, float& lineLogicalLeft, float& lineLogicalRight, float& availableLogicalWidth, IndentTextOrNot shouldIndentText)
{
lineLogicalLeft = block->logicalLeftOffsetForLine(shouldIndentText == IndentText).toFloat();
lineLogicalRight = block->logicalRightOffsetForLine(shouldIndentText == IndentText).toFloat();
availableLogicalWidth = lineLogicalRight - lineLogicalLeft;
}
void RenderParagraph::computeInlineDirectionPositionsForLine(RootInlineBox* lineBox, const LineInfo& lineInfo, BidiRun* firstRun, BidiRun* trailingSpaceRun, bool reachedEnd,
GlyphOverflowAndFallbackFontsMap& textBoxDataMap, VerticalPositionCache& verticalPositionCache, WordMeasurements& wordMeasurements)
{
ETextAlign textAlign = textAlignmentForLine(!reachedEnd && !lineBox->endsWithBreak());
// CSS 2.1: "'Text-indent' only affects a line if it is the first formatted line of an element. For example, the first line of an anonymous block
// box is only affected if it is the first child of its parent element."
// CSS3 "text-indent", "each-line" affects the first line of the block container as well as each line after a forced line break,
// but does not affect lines after a soft wrap break.
bool isFirstLine = lineInfo.isFirstLine();
bool isAfterHardLineBreak = lineBox->prevRootBox() && lineBox->prevRootBox()->endsWithBreak();
IndentTextOrNot shouldIndentText = requiresIndent(isFirstLine, isAfterHardLineBreak, style());
float lineLogicalLeft;
float lineLogicalRight;
float availableLogicalWidth;
updateLogicalInlinePositions(this, lineLogicalLeft, lineLogicalRight, availableLogicalWidth, shouldIndentText);
bool needsWordSpacing;
if (firstRun && firstRun->m_object->isReplaced())
updateLogicalInlinePositions(this, lineLogicalLeft, lineLogicalRight, availableLogicalWidth, shouldIndentText);
computeInlineDirectionPositionsForSegment(lineBox, lineInfo, textAlign, lineLogicalLeft, availableLogicalWidth, firstRun, trailingSpaceRun, textBoxDataMap, verticalPositionCache, wordMeasurements);
// The widths of all runs are now known. We can now place every inline box (and
// compute accurate widths for the inline flow boxes).
needsWordSpacing = false;
lineBox->placeBoxesInInlineDirection(lineLogicalLeft, needsWordSpacing);
}
BidiRun* RenderParagraph::computeInlineDirectionPositionsForSegment(RootInlineBox* lineBox, const LineInfo& lineInfo, ETextAlign textAlign, float& logicalLeft,
float& availableLogicalWidth, BidiRun* firstRun, BidiRun* trailingSpaceRun, GlyphOverflowAndFallbackFontsMap& textBoxDataMap, VerticalPositionCache& verticalPositionCache,
WordMeasurements& wordMeasurements)
{
bool needsWordSpacing = true;
float totalLogicalWidth = lineBox->getFlowSpacingLogicalWidth().toFloat();
unsigned expansionOpportunityCount = 0;
bool isAfterExpansion = true;
Vector<unsigned, 16> expansionOpportunities;
TextJustify textJustify = style()->textJustify();
BidiRun* r = firstRun;
for (; r; r = r->next()) {
if (!r->m_box || r->m_object->isOutOfFlowPositioned() || r->m_box->isLineBreak())
continue; // Positioned objects are only participating to figure out their
// correct static x position. They have no effect on the width.
// Similarly, line break boxes have no effect on the width.
if (r->m_object->isText()) {
RenderText* rt = toRenderText(r->m_object);
if (textAlign == JUSTIFY && r != trailingSpaceRun && textJustify != TextJustifyNone) {
if (!isAfterExpansion)
toInlineTextBox(r->m_box)->setCanHaveLeadingExpansion(true);
unsigned opportunitiesInRun;
if (rt->is8Bit())
opportunitiesInRun = Character::expansionOpportunityCount(rt->characters8() + r->m_start, r->m_stop - r->m_start, r->m_box->direction(), isAfterExpansion);
else
opportunitiesInRun = Character::expansionOpportunityCount(rt->characters16() + r->m_start, r->m_stop - r->m_start, r->m_box->direction(), isAfterExpansion);
expansionOpportunities.append(opportunitiesInRun);
expansionOpportunityCount += opportunitiesInRun;
}
if (rt->textLength()) {
if (!r->m_start && needsWordSpacing && isSpaceOrNewline(rt->characterAt(r->m_start)))
totalLogicalWidth += rt->style(lineInfo.isFirstLine())->font().fontDescription().wordSpacing();
needsWordSpacing = !isSpaceOrNewline(rt->characterAt(r->m_stop - 1));
}
setLogicalWidthForTextRun(lineBox, r, rt, totalLogicalWidth, lineInfo, textBoxDataMap, verticalPositionCache, wordMeasurements);
} else {
isAfterExpansion = false;
if (!r->m_object->isRenderInline()) {
RenderBox* renderBox = toRenderBox(r->m_object);
r->m_box->setLogicalWidth(logicalWidthForChild(renderBox).toFloat());
totalLogicalWidth += marginStartForChild(renderBox) + marginEndForChild(renderBox);
}
}
totalLogicalWidth += r->m_box->logicalWidth();
}
if (isAfterExpansion && !expansionOpportunities.isEmpty()) {
expansionOpportunities.last()--;
expansionOpportunityCount--;
}
updateLogicalWidthForAlignment(textAlign, lineBox, trailingSpaceRun, logicalLeft, totalLogicalWidth, availableLogicalWidth, expansionOpportunityCount);
computeExpansionForJustifiedText(firstRun, trailingSpaceRun, expansionOpportunities, expansionOpportunityCount, totalLogicalWidth, availableLogicalWidth);
return r;
}
void RenderParagraph::computeBlockDirectionPositionsForLine(RootInlineBox* lineBox, BidiRun* firstRun, GlyphOverflowAndFallbackFontsMap& textBoxDataMap,
VerticalPositionCache& verticalPositionCache)
{
setLogicalHeight(lineBox->alignBoxesInBlockDirection(logicalHeight(), textBoxDataMap, verticalPositionCache));
// Now make sure we place replaced render objects correctly.
for (BidiRun* r = firstRun; r; r = r->next()) {
ASSERT(r->m_box);
if (!r->m_box)
continue; // Skip runs with no line boxes.
// Align positioned boxes with the top of the line box. This is
// a reasonable approximation of an appropriate y position.
if (r->m_object->isOutOfFlowPositioned())
r->m_box->setLogicalTop(logicalHeight().toFloat());
// Position is used to properly position both replaced elements and
// to update the static normal flow x/y of positioned elements.
if (r->m_object->isText())
toRenderText(r->m_object)->positionLineBox(r->m_box);
else if (r->m_object->isBox())
toRenderBox(r->m_object)->positionLineBox(r->m_box);
}
}
// This function constructs line boxes for all of the text runs in the resolver and computes their position.
RootInlineBox* RenderParagraph::createLineBoxesFromBidiRuns(unsigned bidiLevel, BidiRunList<BidiRun>& bidiRuns, const InlineIterator& end, LineInfo& lineInfo, VerticalPositionCache& verticalPositionCache, BidiRun* trailingSpaceRun, WordMeasurements& wordMeasurements)
{
if (!bidiRuns.runCount())
return 0;
// FIXME: Why is this only done when we had runs?
lineInfo.setLastLine(!end.object());
RootInlineBox* lineBox = constructLine(bidiRuns, lineInfo);
if (!lineBox)
return 0;
lineBox->setBidiLevel(bidiLevel);
lineBox->setEndsWithBreak(lineInfo.previousLineBrokeCleanly());
GlyphOverflowAndFallbackFontsMap textBoxDataMap;
// Now we position all of our text runs horizontally.
computeInlineDirectionPositionsForLine(lineBox, lineInfo, bidiRuns.firstRun(), trailingSpaceRun, end.atEnd(), textBoxDataMap, verticalPositionCache, wordMeasurements);
// Now position our text runs vertically.
computeBlockDirectionPositionsForLine(lineBox, bidiRuns.firstRun(), textBoxDataMap, verticalPositionCache);
// Compute our overflow now.
lineBox->computeOverflow(lineBox->lineTop(), lineBox->lineBottom(), textBoxDataMap);
return lineBox;
}
static void deleteLineRange(LineLayoutState& layoutState, RootInlineBox* startLine, RootInlineBox* stopLine = 0)
{
RootInlineBox* boxToDelete = startLine;
while (boxToDelete && boxToDelete != stopLine) {
// Note: deleteLineRange(firstRootBox()) is not identical to deleteLineBoxTree().
// deleteLineBoxTree uses nextLineBox() instead of nextRootBox() when traversing.
RootInlineBox* next = boxToDelete->nextRootBox();
boxToDelete->deleteLine();
boxToDelete = next;
}
}
void RenderParagraph::layoutRunsAndFloats(LineLayoutState& layoutState)
{
// We want to skip ahead to the first dirty line
InlineBidiResolver resolver;
RootInlineBox* startLine = determineStartPosition(layoutState, resolver);
// We also find the first clean line and extract these lines. We will add them back
// if we determine that we're able to synchronize after handling all our dirty lines.
InlineIterator cleanLineStart;
BidiStatus cleanLineBidiStatus;
if (!layoutState.isFullLayout() && startLine)
determineEndPosition(layoutState, startLine, cleanLineStart, cleanLineBidiStatus);
if (startLine)
deleteLineRange(layoutState, startLine);
layoutRunsAndFloatsInRange(layoutState, resolver, cleanLineStart, cleanLineBidiStatus);
linkToEndLineIfNeeded(layoutState);
}
void RenderParagraph::layoutRunsAndFloatsInRange(LineLayoutState& layoutState,
InlineBidiResolver& resolver, const InlineIterator& cleanLineStart,
const BidiStatus& cleanLineBidiStatus)
{
RenderStyle* styleToUse = style();
LineMidpointState& lineMidpointState = resolver.midpointState();
InlineIterator endOfLine = resolver.position();
bool checkForEndLineMatch = layoutState.endLine();
RenderTextInfo renderTextInfo;
VerticalPositionCache verticalPositionCache;
LineBreaker lineBreaker(this);
while (!endOfLine.atEnd()) {
// FIXME: Is this check necessary before the first iteration or can it be moved to the end?
if (checkForEndLineMatch) {
layoutState.setEndLineMatched(matchedEndLine(layoutState, resolver, cleanLineStart, cleanLineBidiStatus));
if (layoutState.endLineMatched()) {
resolver.setPosition(InlineIterator(resolver.position().root(), 0, 0), 0);
break;
}
}
lineMidpointState.reset();
layoutState.lineInfo().setEmpty(true);
layoutState.lineInfo().resetRunsFromLeadingWhitespace();
bool isNewUBAParagraph = layoutState.lineInfo().previousLineBrokeCleanly();
FloatingObject* lastFloatFromPreviousLine = 0;
WordMeasurements wordMeasurements;
endOfLine = lineBreaker.nextLineBreak(resolver, layoutState.lineInfo(), renderTextInfo,
lastFloatFromPreviousLine, wordMeasurements);
renderTextInfo.m_lineBreakIterator.resetPriorContext();
if (resolver.position().atEnd()) {
// FIXME: We shouldn't be creating any runs in nextLineBreak to begin with!
// Once BidiRunList is separated from BidiResolver this will not be needed.
resolver.runs().deleteRuns();
resolver.markCurrentRunEmpty(); // FIXME: This can probably be replaced by an ASSERT (or just removed).
resolver.setPosition(InlineIterator(resolver.position().root(), 0, 0), 0);
break;
}
ASSERT(endOfLine != resolver.position());
// This is a short-cut for empty lines.
if (layoutState.lineInfo().isEmpty()) {
if (lastRootBox())
lastRootBox()->setLineBreakInfo(endOfLine.object(), endOfLine.offset(), resolver.status());
} else {
VisualDirectionOverride override = (styleToUse->rtlOrdering() == VisualOrder ? (styleToUse->direction() == LTR ? VisualLeftToRightOverride : VisualRightToLeftOverride) : NoVisualOverride);
if (isNewUBAParagraph && styleToUse->unicodeBidi() == Plaintext && !resolver.context()->parent()) {
TextDirection direction = determinePlaintextDirectionality(resolver.position().root(), resolver.position().object(), resolver.position().offset());
resolver.setStatus(BidiStatus(direction, isOverride(styleToUse->unicodeBidi())));
}
// FIXME: This ownership is reversed. We should own the BidiRunList and pass it to createBidiRunsForLine.
BidiRunList<BidiRun>& bidiRuns = resolver.runs();
constructBidiRunsForLine(resolver, bidiRuns, endOfLine, override, layoutState.lineInfo().previousLineBrokeCleanly(), isNewUBAParagraph);
ASSERT(resolver.position() == endOfLine);
BidiRun* trailingSpaceRun = resolver.trailingSpaceRun();
if (bidiRuns.runCount() && lineBreaker.lineWasHyphenated())
bidiRuns.logicallyLastRun()->m_hasHyphen = true;
// Now that the runs have been ordered, we create the line boxes.
// At the same time we figure out where border/padding/margin should be applied for
// inline flow boxes.
RootInlineBox* lineBox = createLineBoxesFromBidiRuns(resolver.status().context->level(), bidiRuns, endOfLine, layoutState.lineInfo(), verticalPositionCache, trailingSpaceRun, wordMeasurements);
bidiRuns.deleteRuns();
resolver.markCurrentRunEmpty(); // FIXME: This can probably be replaced by an ASSERT (or just removed).
if (lineBox)
lineBox->setLineBreakInfo(endOfLine.object(), endOfLine.offset(), resolver.status());
}
if (!layoutState.lineInfo().isEmpty())
layoutState.lineInfo().setFirstLine(false);
lineMidpointState.reset();
resolver.setPosition(endOfLine, numberOfIsolateAncestors(endOfLine));
}
}
void RenderParagraph::linkToEndLineIfNeeded(LineLayoutState& layoutState)
{
if (layoutState.endLine()) {
if (layoutState.endLineMatched()) {
// Attach all the remaining lines, and then adjust their y-positions as needed.
LayoutUnit delta = logicalHeight() - layoutState.endLineLogicalTop();
for (RootInlineBox* line = layoutState.endLine(); line; line = line->nextRootBox()) {
line->attachLine();
if (delta)
line->adjustBlockDirectionPosition(delta.toFloat());
}
setLogicalHeight(lastRootBox()->lineBottomWithLeading());
} else {
// Delete all the remaining lines.
deleteLineRange(layoutState, layoutState.endLine());
}
}
}
struct InlineMinMaxIterator {
/* InlineMinMaxIterator is a class that will iterate over all render objects that contribute to
inline min/max width calculations. Note the following about the way it walks:
(1) Positioned content is skipped (since it does not contribute to min/max width of a block)
(2) We do not drill into the children of floats or replaced elements, since you can't break
in the middle of such an element.
(3) Inline flows (e.g., <a>, <span>, <i>) are walked twice, since each side can have
distinct borders/margin/padding that contribute to the min/max width.
*/
RenderObject* parent;
RenderObject* current;
bool endOfInline;
InlineMinMaxIterator(RenderObject* p)
: parent(p), current(p), endOfInline(false)
{
}
RenderObject* next();
};
RenderObject* InlineMinMaxIterator::next()
{
RenderObject* result = 0;
bool oldEndOfInline = endOfInline;
endOfInline = false;
while (current || current == parent) {
if (!oldEndOfInline && (current == parent || (!current->isReplaced() && !current->isOutOfFlowPositioned())))
result = current->slowFirstChild();
if (!result) {
// We hit the end of our inline. (It was empty, e.g., <span></span>.)
if (!oldEndOfInline && current->isRenderInline()) {
result = current;
endOfInline = true;
break;
}
while (current && current != parent) {
result = current->nextSibling();
if (result)
break;
current = current->parent();
if (current && current != parent && current->isRenderInline()) {
result = current;
endOfInline = true;
break;
}
}
}
if (!result)
break;
if (!result->isOutOfFlowPositioned() && (result->isText() || result->isReplaced() || result->isRenderInline()))
break;
current = result;
result = 0;
}
// Update our position.
current = result;
return current;
}
static LayoutUnit getBPMWidth(LayoutUnit childValue, Length cssUnit)
{
if (cssUnit.type() != Auto)
return (cssUnit.isFixed() ? static_cast<LayoutUnit>(cssUnit.value()) : childValue);
return 0;
}
static LayoutUnit getBorderPaddingMargin(RenderBoxModelObject* child, bool endOfInline)
{
RenderStyle* childStyle = child->style();
if (endOfInline) {
return getBPMWidth(child->marginEnd(), childStyle->marginEnd()) +
getBPMWidth(child->paddingEnd(), childStyle->paddingEnd()) +
child->borderEnd();
}
return getBPMWidth(child->marginStart(), childStyle->marginStart()) +
getBPMWidth(child->paddingStart(), childStyle->paddingStart()) +
child->borderStart();
}
static inline void stripTrailingSpace(float& inlineMax, float& inlineMin, RenderObject* trailingSpaceChild)
{
if (trailingSpaceChild && trailingSpaceChild->isText()) {
// Collapse away the trailing space at the end of a block.
RenderText* t = toRenderText(trailingSpaceChild);
const UChar space = ' ';
const Font& font = t->style()->font(); // FIXME: This ignores first-line.
float spaceWidth = font.width(constructTextRun(t, font, &space, 1, t->style(), LTR));
inlineMax -= spaceWidth + font.fontDescription().wordSpacing();
if (inlineMin > inlineMax)
inlineMin = inlineMax;
}
}
static inline void updatePreferredWidth(LayoutUnit& preferredWidth, float& result)
{
LayoutUnit snappedResult = LayoutUnit::fromFloatCeil(result);
preferredWidth = std::max(snappedResult, preferredWidth);
}
// When converting between floating point and LayoutUnits we risk losing precision
// with each conversion. When this occurs while accumulating our preferred widths,
// we can wind up with a line width that's larger than our maxPreferredWidth due to
// pure float accumulation.
static inline LayoutUnit adjustFloatForSubPixelLayout(float value)
{
return LayoutUnit::fromFloatCeil(value);
}
// FIXME: This function should be broken into something less monolithic.
// FIXME: The main loop here is very similar to LineBreaker::nextSegmentBreak. They can probably reuse code.
void RenderParagraph::computeIntrinsicLogicalWidths(LayoutUnit& minLogicalWidth, LayoutUnit& maxLogicalWidth) const
{
float inlineMax = 0;
float inlineMin = 0;
RenderStyle* styleToUse = style();
RenderBlock* containingBlock = this->containingBlock();
LayoutUnit cw = containingBlock ? containingBlock->contentLogicalWidth() : LayoutUnit();
// If we are at the start of a line, we want to ignore all white-space.
// Also strip spaces if we previously had text that ended in a trailing space.
bool stripFrontSpaces = true;
RenderObject* trailingSpaceChild = 0;
bool autoWrap, oldAutoWrap;
autoWrap = oldAutoWrap = styleToUse->autoWrap();
InlineMinMaxIterator childIterator(const_cast<RenderParagraph*>(this));
// Only gets added to the max preffered width once.
bool addedTextIndent = false;
// Signals the text indent was more negative than the min preferred width
bool hasRemainingNegativeTextIndent = false;
LayoutUnit textIndent = minimumValueForLength(styleToUse->textIndent(), cw);
bool isPrevChildInlineFlow = false;
bool shouldBreakLineAfterText = false;
while (RenderObject* child = childIterator.next()) {
autoWrap = child->isReplaced() ? child->parent()->style()->autoWrap() :
child->style()->autoWrap();
// Step One: determine whether or not we need to go ahead and
// terminate our current line. Each discrete chunk can become
// the new min-width, if it is the widest chunk seen so far, and
// it can also become the max-width.
// Children fall into three categories:
// (1) An inline flow object. These objects always have a min/max of 0,
// and are included in the iteration solely so that their margins can
// be added in.
//
// (2) An inline non-text non-flow object, e.g., an inline replaced element.
// These objects can always be on a line by themselves, so in this situation
// we need to go ahead and break the current line, and then add in our own
// margins and min/max width on its own line, and then terminate the line.
//
// (3) A text object. Text runs can have breakable characters at the start,
// the middle or the end. They may also lose whitespace off the front if
// we're already ignoring whitespace. In order to compute accurate min-width
// information, we need three pieces of information.
// (a) the min-width of the first non-breakable run. Should be 0 if the text string
// starts with whitespace.
// (b) the min-width of the last non-breakable run. Should be 0 if the text string
// ends with whitespace.
// (c) the min/max width of the string (trimmed for whitespace).
//
// If the text string starts with whitespace, then we need to go ahead and
// terminate our current line (unless we're already in a whitespace stripping
// mode.
//
// If the text string has a breakable character in the middle, but didn't start
// with whitespace, then we add the width of the first non-breakable run and
// then end the current line. We then need to use the intermediate min/max width
// values (if any of them are larger than our current min/max). We then look at
// the width of the last non-breakable run and use that to start a new line
// (unless we end in whitespace).
RenderStyle* childStyle = child->style();
float childMin = 0;
float childMax = 0;
if (!child->isText()) {
// Case (1) and (2). Inline replaced and inline flow elements.
if (child->isRenderInline()) {
// Add in padding/border/margin from the appropriate side of
// the element.
float bpm = getBorderPaddingMargin(toRenderInline(child), childIterator.endOfInline).toFloat();
childMin += bpm;
childMax += bpm;
inlineMin += childMin;
inlineMax += childMax;
child->clearPreferredLogicalWidthsDirty();
} else {
// Inline replaced elts add in their margins to their min/max values.
LayoutUnit margins = 0;
Length startMargin = childStyle->marginStart();
Length endMargin = childStyle->marginEnd();
if (startMargin.isFixed())
margins += adjustFloatForSubPixelLayout(startMargin.value());
if (endMargin.isFixed())
margins += adjustFloatForSubPixelLayout(endMargin.value());
childMin += margins.ceilToFloat();
childMax += margins.ceilToFloat();
}
}
if (!child->isRenderInline() && !child->isText()) {
// Case (2). Inline replaced elements and floats.
// Go ahead and terminate the current line as far as
// minwidth is concerned.
LayoutUnit childMinPreferredLogicalWidth = child->minPreferredLogicalWidth();
LayoutUnit childMaxPreferredLogicalWidth = child->maxPreferredLogicalWidth();
childMin += childMinPreferredLogicalWidth.ceilToFloat();
childMax += childMaxPreferredLogicalWidth.ceilToFloat();
bool canBreakReplacedElement = true;
if ((canBreakReplacedElement && (autoWrap || oldAutoWrap) && (!isPrevChildInlineFlow || shouldBreakLineAfterText))) {
updatePreferredWidth(minLogicalWidth, inlineMin);
inlineMin = 0;
}
// Add in text-indent. This is added in only once.
if (!addedTextIndent) {
float ceiledTextIndent = textIndent.ceilToFloat();
childMin += ceiledTextIndent;
childMax += ceiledTextIndent;
if (childMin < 0)
textIndent = adjustFloatForSubPixelLayout(childMin);
else
addedTextIndent = true;
}
// Add our width to the max.
inlineMax += std::max<float>(0, childMax);
if (!autoWrap || !canBreakReplacedElement || (isPrevChildInlineFlow && !shouldBreakLineAfterText)) {
inlineMin += childMin;
} else {
// Now check our line.
updatePreferredWidth(minLogicalWidth, childMin);
// Now start a new line.
inlineMin = 0;
}
if (autoWrap && canBreakReplacedElement && isPrevChildInlineFlow) {
updatePreferredWidth(minLogicalWidth, inlineMin);
inlineMin = 0;
}
// We are no longer stripping whitespace at the start of
// a line.
stripFrontSpaces = false;
trailingSpaceChild = 0;
} else if (child->isText()) {
// Case (3). Text.
RenderText* t = toRenderText(child);
// Determine if we have a breakable character. Pass in
// whether or not we should ignore any spaces at the front
// of the string. If those are going to be stripped out,
// then they shouldn't be considered in the breakable char
// check.
bool hasBreakableChar, hasBreak;
float firstLineMinWidth, lastLineMinWidth;
bool hasBreakableStart, hasBreakableEnd;
float firstLineMaxWidth, lastLineMaxWidth;
t->trimmedPrefWidths(inlineMax,
firstLineMinWidth, hasBreakableStart, lastLineMinWidth, hasBreakableEnd,
hasBreakableChar, hasBreak, firstLineMaxWidth, lastLineMaxWidth,
childMin, childMax, stripFrontSpaces, styleToUse->direction());
// This text object will not be rendered, but it may still provide a breaking opportunity.
if (!hasBreak && !childMax) {
if (autoWrap && (hasBreakableStart || hasBreakableEnd)) {
updatePreferredWidth(minLogicalWidth, inlineMin);
inlineMin = 0;
}
continue;
}
if (stripFrontSpaces)
trailingSpaceChild = child;
else
trailingSpaceChild = 0;
// Add in text-indent. This is added in only once.
float ti = 0;
if (!addedTextIndent || hasRemainingNegativeTextIndent) {
ti = textIndent.ceilToFloat();
childMin += ti;
firstLineMinWidth += ti;
// It the text indent negative and larger than the child minimum, we re-use the remainder
// in future minimum calculations, but using the negative value again on the maximum
// will lead to under-counting the max pref width.
if (!addedTextIndent) {
childMax += ti;
firstLineMaxWidth += ti;
addedTextIndent = true;
}
if (childMin < 0) {
textIndent = childMin;
hasRemainingNegativeTextIndent = true;
}
}
// If we have no breakable characters at all,
// then this is the easy case. We add ourselves to the current
// min and max and continue.
if (!hasBreakableChar) {
inlineMin += childMin;
} else {
if (hasBreakableStart) {
updatePreferredWidth(minLogicalWidth, inlineMin);
} else {
inlineMin += firstLineMinWidth;
updatePreferredWidth(minLogicalWidth, inlineMin);
childMin -= ti;
}
inlineMin = childMin;
if (hasBreakableEnd) {
updatePreferredWidth(minLogicalWidth, inlineMin);
inlineMin = 0;
shouldBreakLineAfterText = false;
} else {
updatePreferredWidth(minLogicalWidth, inlineMin);
inlineMin = lastLineMinWidth;
shouldBreakLineAfterText = true;
}
}
if (hasBreak) {
inlineMax += firstLineMaxWidth;
updatePreferredWidth(maxLogicalWidth, inlineMax);
updatePreferredWidth(maxLogicalWidth, childMax);
inlineMax = lastLineMaxWidth;
addedTextIndent = true;
} else {
inlineMax += std::max<float>(0, childMax);
}
}
if (!child->isText() && child->isRenderInline())
isPrevChildInlineFlow = true;
else
isPrevChildInlineFlow = false;
oldAutoWrap = autoWrap;
}
if (styleToUse->collapseWhiteSpace())
stripTrailingSpace(inlineMax, inlineMin, trailingSpaceChild);
updatePreferredWidth(minLogicalWidth, inlineMin);
updatePreferredWidth(maxLogicalWidth, inlineMax);
maxLogicalWidth = std::max(minLogicalWidth, maxLogicalWidth);
}
int RenderParagraph::firstLineBoxBaseline(FontBaselineOrAuto baselineType) const
{
if (!firstLineBox())
return -1;
FontBaseline baseline;
if (baselineType.m_auto)
baseline = firstRootBox()->baselineType();
else
baseline = baselineType.m_baseline;
return firstLineBox()->logicalTop() + style(true)->fontMetrics().ascent(baseline);
}
int RenderParagraph::lastLineBoxBaseline(LineDirectionMode lineDirection) const
{
if (!firstLineBox() && hasLineIfEmpty()) {
const FontMetrics& fontMetrics = firstLineStyle()->fontMetrics();
return fontMetrics.ascent()
+ (lineHeight(true, lineDirection, PositionOfInteriorLineBoxes) - fontMetrics.height()) / 2
+ (lineDirection == HorizontalLine ? borderTop() + paddingTop() : borderRight() + paddingRight());
}
if (lastLineBox())
return lastLineBox()->logicalTop() + style(lastLineBox() == firstLineBox())->fontMetrics().ascent(lastRootBox()->baselineType());
return -1;
}
void RenderParagraph::layout()
{
ASSERT(needsLayout());
ASSERT(isInlineBlock() || !isInline());
if (simplifiedLayout())
return;
SubtreeLayoutScope layoutScope(*this);
LayoutUnit oldLeft = logicalLeft();
bool logicalWidthChanged = updateLogicalWidthAndColumnWidth();
bool relayoutChildren = logicalWidthChanged;
LayoutUnit beforeEdge = borderBefore() + paddingBefore();
LayoutUnit afterEdge = borderAfter() + paddingAfter();
LayoutUnit previousHeight = logicalHeight();
setLogicalHeight(beforeEdge);
layoutChildren(relayoutChildren, layoutScope, beforeEdge, afterEdge);
LayoutUnit oldClientAfterEdge = clientLogicalBottom();
updateLogicalHeight();
if (previousHeight != logicalHeight())
relayoutChildren = true;
layoutPositionedObjects(relayoutChildren, oldLeft != logicalLeft() ? ForcedLayoutAfterContainingBlockMoved : DefaultLayout);
// Add overflow from children (unless we're multi-column, since in that case all our child overflow is clipped anyway).
computeOverflow(oldClientAfterEdge);
updateLayerTransformAfterLayout();
clearNeedsLayout();
}
void RenderParagraph::layoutChildren(bool relayoutChildren, SubtreeLayoutScope& layoutScope, LayoutUnit beforeEdge, LayoutUnit afterEdge)
{
// Figure out if we should clear out our line boxes.
// FIXME: Handle resize eventually!
bool isFullLayout = !firstLineBox() || selfNeedsLayout() || relayoutChildren;
LineLayoutState layoutState(isFullLayout);
if (isFullLayout)
lineBoxes()->deleteLineBoxes();
if (firstChild()) {
// In full layout mode, clear the line boxes of children upfront. Otherwise,
// siblings can run into stale root lineboxes during layout. Then layout
// the replaced elements later. In partial layout mode, line boxes are not
// deleted and only dirtied. In that case, we can layout the replaced
// elements at the same time.
Vector<RenderBox*> replacedChildren;
for (InlineWalker walker(this); !walker.atEnd(); walker.advance()) {
RenderObject* o = walker.current();
if (!layoutState.hasInlineChild() && o->isInline())
layoutState.setHasInlineChild(true);
if (o->isReplaced() || o->isOutOfFlowPositioned()) {
RenderBox* box = toRenderBox(o);
updateBlockChildDirtyBitsBeforeLayout(relayoutChildren, box);
if (o->isOutOfFlowPositioned()) {
o->containingBlock()->insertPositionedObject(box);
} else if (isFullLayout || o->needsLayout()) {
// Replaced element.
box->dirtyLineBoxes(isFullLayout);
if (isFullLayout)
replacedChildren.append(box);
else
o->layoutIfNeeded();
}
} else if (o->isText() || (o->isRenderInline() && !walker.atEndOfInline())) {
if (!o->isText())
toRenderInline(o)->updateAlwaysCreateLineBoxes(layoutState.isFullLayout());
if (layoutState.isFullLayout() || o->selfNeedsLayout())
dirtyLineBoxesForRenderer(o, layoutState.isFullLayout());
o->clearNeedsLayout();
}
}
for (size_t i = 0; i < replacedChildren.size(); i++)
replacedChildren[i]->layoutIfNeeded();
layoutRunsAndFloats(layoutState);
}
// Expand the last line to accommodate Ruby and emphasis marks.
int lastLineAnnotationsAdjustment = 0;
if (lastRootBox()) {
LayoutUnit lowestAllowedPosition = std::max(lastRootBox()->lineBottom(), logicalHeight() + paddingAfter());
lastLineAnnotationsAdjustment = lastRootBox()->computeUnderAnnotationAdjustment(lowestAllowedPosition);
}
// Now add in the bottom border/padding.
setLogicalHeight(logicalHeight() + lastLineAnnotationsAdjustment + afterEdge);
if (!firstLineBox() && hasLineIfEmpty())
setLogicalHeight(logicalHeight() + lineHeight(true, HorizontalLine, PositionOfInteriorLineBoxes));
}
RootInlineBox* RenderParagraph::determineStartPosition(LineLayoutState& layoutState, InlineBidiResolver& resolver)
{
RootInlineBox* curr = 0;
RootInlineBox* last = 0;
if (layoutState.isFullLayout()) {
// If we encountered a new float and have inline children, mark ourself to force us to issue paint invalidations.
if (layoutState.hasInlineChild() && !selfNeedsLayout()) {
setNeedsLayout(MarkOnlyThis);
}
// FIXME: This should just call deleteLineBoxTree, but that causes
// crashes for fast/repaint tests.
curr = firstRootBox();
while (curr) {
// Note: This uses nextRootBox() insted of nextLineBox() like deleteLineBoxTree does.
RootInlineBox* next = curr->nextRootBox();
curr->deleteLine();
curr = next;
}
ASSERT(!firstLineBox() && !lastLineBox());
} else {
if (curr) {
// We have a dirty line.
if (RootInlineBox* prevRootBox = curr->prevRootBox()) {
// We have a previous line.
if (!prevRootBox->endsWithBreak() || !prevRootBox->lineBreakObj() || (prevRootBox->lineBreakObj()->isText() && prevRootBox->lineBreakPos() >= toRenderText(prevRootBox->lineBreakObj())->textLength()))
// The previous line didn't break cleanly or broke at a newline
// that has been deleted, so treat it as dirty too.
curr = prevRootBox;
}
} else {
// No dirty lines were found.
// If the last line didn't break cleanly, treat it as dirty.
if (lastRootBox() && !lastRootBox()->endsWithBreak())
curr = lastRootBox();
}
// If we have no dirty lines, then last is just the last root box.
last = curr ? curr->prevRootBox() : lastRootBox();
}
layoutState.lineInfo().setFirstLine(!last);
layoutState.lineInfo().setPreviousLineBrokeCleanly(!last || last->endsWithBreak());
if (last) {
setLogicalHeight(last->lineBottomWithLeading());
InlineIterator iter = InlineIterator(this, last->lineBreakObj(), last->lineBreakPos());
resolver.setPosition(iter, numberOfIsolateAncestors(iter));
resolver.setStatus(last->lineBreakBidiStatus());
} else {
TextDirection direction = style()->direction();
if (style()->unicodeBidi() == Plaintext)
direction = determinePlaintextDirectionality(this);
resolver.setStatus(BidiStatus(direction, isOverride(style()->unicodeBidi())));
InlineIterator iter = InlineIterator(this, bidiFirstSkippingEmptyInlines(this, resolver.runs(), &resolver), 0);
resolver.setPosition(iter, numberOfIsolateAncestors(iter));
}
return curr;
}
void RenderParagraph::determineEndPosition(LineLayoutState& layoutState, RootInlineBox* startLine, InlineIterator& cleanLineStart, BidiStatus& cleanLineBidiStatus)
{
ASSERT(!layoutState.endLine());
RootInlineBox* last = 0;
for (RootInlineBox* curr = startLine->nextRootBox(); curr; curr = curr->nextRootBox()) {
if (curr->isDirty())
last = 0;
else if (!last)
last = curr;
}
if (!last)
return;
// At this point, |last| is the first line in a run of clean lines that ends with the last line
// in the block.
RootInlineBox* prev = last->prevRootBox();
cleanLineStart = InlineIterator(this, prev->lineBreakObj(), prev->lineBreakPos());
cleanLineBidiStatus = prev->lineBreakBidiStatus();
layoutState.setEndLineLogicalTop(prev->lineBottomWithLeading());
for (RootInlineBox* line = last; line; line = line->nextRootBox())
line->extractLine(); // Disconnect all line boxes from their render objects while preserving
// their connections to one another.
layoutState.setEndLine(last);
}
bool RenderParagraph::checkPaginationAndFloatsAtEndLine(LineLayoutState& layoutState)
{
// FIXME(sky): Remove this.
return true;
}
bool RenderParagraph::matchedEndLine(LineLayoutState& layoutState, const InlineBidiResolver& resolver, const InlineIterator& endLineStart, const BidiStatus& endLineStatus)
{
if (resolver.position() == endLineStart) {
if (resolver.status() != endLineStatus)
return false;
return checkPaginationAndFloatsAtEndLine(layoutState);
}
// The first clean line doesn't match, but we can check a handful of following lines to try
// to match back up.
static int numLines = 8; // The # of lines we're willing to match against.
RootInlineBox* originalEndLine = layoutState.endLine();
RootInlineBox* line = originalEndLine;
for (int i = 0; i < numLines && line; i++, line = line->nextRootBox()) {
if (line->lineBreakObj() == resolver.position().object() && line->lineBreakPos() == resolver.position().offset()) {
// We have a match.
if (line->lineBreakBidiStatus() != resolver.status())
return false; // ...but the bidi state doesn't match.
bool matched = false;
RootInlineBox* result = line->nextRootBox();
layoutState.setEndLine(result);
if (result) {
layoutState.setEndLineLogicalTop(line->lineBottomWithLeading());
matched = checkPaginationAndFloatsAtEndLine(layoutState);
}
// Now delete the lines that we failed to sync.
deleteLineRange(layoutState, originalEndLine, result);
return matched;
}
}
return false;
}
} // namespace blink
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